Biopsych

Question 1

What makes up the nervous system?

Answer 1

The brain and the spinal cord

Question 2

What does the peripheral nervous system do?

Answer 2

Relays messages from the environment to the CNS via sensory neurones and from the CNS to effectors via motor neurons.

Question 3

PNS is further subdivided into the autonomic nervous system and the somatic nervous system, what role do each of these systems play?

Answer 3

ANS- controls involuntary, vital functions of the body such as maintaining heart rates and breathing rates.
SNS- receives info from sensory receptors belonging to each of the 5 senses and results in stimulation by the CNS via motor neurons.

Question 4

Autonomic nervous system is divided into 2 branches: explain

Answer 4

Sympathetic- increases heart rates, pupil dilation Parasympathetic- produces physiological arousal needed to maintain the fight or flight response.

Question 5

Outline the endocrine system

Answer 5

Main chemical messenger system of the body, where hormones are secreted into the bloodstream from glands and then are transported towards target cells in the blood with complementary receptors.

Question 6

Outline the pituitary gland

Answer 6

“Master gland”
Controls the release of hormones from all other glands in the body. Eg thyroid gland releases the hormone thyroxine, which increases heart rate and increases the rate of growth.

Question 7

Outline the adrenal gland

Answer 7

Releases adrenaline which creates the fight or flight response

Question 8

Outline the fight or flight response in 5 stages

Answer 8

1. Body senses stressor in the environment
2. Sensory receptors in the Parasympathetic Nervous System send the info to the Hypothalamus. The hypothalamus co ordinates a response and triggers increased levels of activity in the sympathetic branch of the ANS
3. Adrenaline is released from the adrenal medulla (in the adrenal glands). It is transported towards target cells target effectors via the blood
4. Saliva production inhibited & faster breathing rate.
5. Once the stressor is no longer a threat, hypothalamus triggers less activity in the sympathetic branch & more in the parasympathetic branch of the ANS (“rest and digest response”)

Question 9

Outline the 4 stage process of synaptic transmission

Answer 9

1. Action potential arrives at the presynaptic membrane
2. Increased concentration in the membrane causes vesicles (contains the neurotransmitter) to fuse with the presynaptic membrane & release the neurotransmitter into the synaptic cleft.
3. Neurotransmitter diffuses across the synapse resulting in an inhibitory or excitatory effect in the post synaptic membrane.
4. Resulting action potential is transmitted along the axon to the next neuron

Question 10

Localisation theory

Answer 10

Certain areas are responsible for certain processes, behaviours and activities

Question 11

Motor area

Answer 11

Found in the frontal lobe
Involved in regulating & co ordinating movements
Damage results in an inability to do this

Question 12

Auditory area

Answer 12

Area of the temporal lobe
Responsible for processing auditory information and speech
Damage causes hearing loss

Question 13

Visual area

Answer 13

Area of the occipital lobe
Responsible for processing visual information

Question 14

Somatosensory area

Answer 14

Area of the parietal lobe which processes info to do with the senses.
Damage causes loss of sensitivity to particular bodily areas like the tip of your fingers

Question 15

Wernickes area

Answer 15

Responsible for speech comprehension
Located in the temporal lobe
Damage results in “Wernicke’s aphasia” which is characterised by the use of nonsensical words, no awareness of using incorrect words

Question 16

Broca’s area

Answer 16

Responsible for speech production
Located in the frontal lobe
Damage results in Broca’s aphasia , charectrised by difficulty forming complete sentences & understanding sentences

Question 17

Supporting evidence for localisation of brain function: Tulving et al

Answer 17

Used PET scans
Found semantic memories were recalled from the left prefrontal cortex whilst episodic memories were recalled from the right prefrontal cortex.
This shows that different areas of the brain are responsible for different functions, as predicted by the localisation of function theory.

Question 18

Phineas Gage: support for localisation

Answer 18

Blasting rod tore through his prefrontal cortex, damaged both cortices.
Lost the ability to make rational decisions and process emotions.
This supports the idea that different parts of the brain are responsible for different functions.

Question 19

Lashley

Question 20

Plasticity definition

Answer 20

Brain’s ability to physically & functionally adapt and change in response to trauma, new experinces and learning.
Opposes original theory that there is a critical window for synaptic and neuronal connection formation.

Question 21

Synaptic pruning

Answer 21

Process which extra neurons & synaptic connections are killed to increase the efficiency of neuronal transmissions.
Controls strength & number of neuronal connections

Question 22

Maguire et al

Answer 22

After studying brain’s of taxi drivers, found a larger gre matter volume in the mid posterior hippocampi of their brains.
Also found a positive correlation between an increasing grey matter volume the longer the individual had been a taxi driver.
The hippocampus is associated with spatial awareness, an ability taxi drivers must have to pass “The Knowledge Test”

Question 23

Define functional recovery

Answer 23

Ability of the brain to transfer functions of the damaged area to other healthy functioning parts of the brain, allowing normal functioning to continue.
Enabled through: law of equipotentiality (secondary neural circuits surrounding the damaged area become activated)
Axonal sprouting (formation of new synapses & strengthening of axonal connections between the damaged and healthy area)
Means functions are not always lateralised to specific hemispheres

Question 24

Real life support for the positive effects of neuroplasticity

Answer 24

Jodi Miller
Entire right hemisphere was removed to control her epileptic seizures. Through neuroplasticity she was able to control the right side of her body through the use of cerebral spinal fluid.

Question 25

Hemispheric lateralisation

Answer 25

The idea that each hemisphere of the brain is mainly responsible for certain behaviours

Question 26

Outline Sperry’s research

Answer 26

Conducted lab experiment split brain research on 11 epileptic patients, in order to cope with the seizures, the patients had gone through a surgical lesioning of their corpus callosum. 1. Patients had one of their eyes covered so that info would not be recieved by both eyes. 2. Stimuli flashed onto a screen for less than a second.

Question 27

Evaluation for sperry: 2 weaknesses

Answer 27

1. Lack of control with the sample. Epileptic patients had been taking medications for different periods of time, which may have affected their ability to recognise objects and match words, due to neuronal changes. 2. Differences in lesioning. There may have been differences in the exact amount of the corpus callosum that was lesioned. Confounding variables weren’t controlled.

Question 28

Evaluation Sperry: Strength

Answer 28

1. Clearly demonstrated lateralisation of function. Split brain research was crucial in establishing differences in functions between the 2 hemispheres.

Question 29

fMRI scans define, strength, weakness

Answer 29

Def: Areas of the brain with high levels of activity have a largers requirement for oxygenated blood, leading to a higher rate of blood deoxygenation. The highly active areas absorbs the signal produced by the scan, they appear brightly coloured on the screen. Strength: High spatial resolution, doesn’t use ionising radiation, can be used whilst a patient is carrying out a task Weakness: poor temporal resolution

Question 30

EEG scans: def, strengths, weakness

Answer 30

Def. Electrodes attached to scalp, measures & amplifies the electric activity across the whole brain like action potentials. Strength: Used to discover the different stages of sleep, higher temporal resolution Weakness: lower spatial resolution compared to fMRI scans

Question 31

Post mortem examinations: def, strength, weakness

Answer 31

Def. These involve a comparison of patient’s brain with a healthy, neurotypical brain. Any differences are assumed to have caused the neurological problem the patient faced in their lifetime. Strength: useful for advancing medical knowledge eg Broca used PME on Tan. Weakness: Ethical issues (informed consent) based on assumptions

Question 32

Biological Rhythms

Answer 32

Periodic biological fluctuations in an organism that acts in response to periodic environmental change Eg. Include changes in core bodily temperature and sleep wake cycle

Question 33

Endogenous vs Exogenous

Answer 33

Endogenous pacemakers: controlled by internal clocks eg Suprachriasmatic nucleus Exogenous zeitgebers: external changes in the environment which affect or entrain our biological rhythms eg light, changes in light exposure can trigger desynchronisation of a pre set sleep-wake cycle

Question 34

Circadian rhythms

Answer 34

A type of biological rhythm which completes one full cycle 24 hours, it is affected by both endogenous pacemakers and exogenous zeitgebers

Question 35

Siffre study

Answer 35

1. Who stayed in a cave completely devoid of natural light. 2. His sleep-wake cycle didnt conform to 24 hours but was around 24 & 30 minutes. 3. This demonstrates that there was an internal clock independent of natural day/night cycle. 4. Describes a “free running” circadian rhythm which is not affected by exogenous zeitgebers

Question 36

Aschoff and Wever study

Answer 36

55 ppts were deprived of natural light whilst spending 4 weeks in an underground bunker. Researchers found that all subjects showed free running circadian rhythms with the average periods of wakefulness and sleep ranging from 23.9 to 50 hours. Majority of the ppts remained internally synchronised during the whole experiment. These findings demonstrate the free running circadian rhythms is more than 24 hours long as a society we have specific exogenous Zeitgebers which entrain the rhythm to conform to a 24 hour cycle.

Question 37

Evaluation for research into exogenous Zeitgebers

Answer 37

1. Confounding variable, artifical lighting can create shifts in circadian rhythm by up to 6 hours. Siffries research was conducted at a time where researchers believed that artifical lighting had no effect on biological rhythms. The use of artifical light mean that over 2 months Siffre could have entrained his own rhythms through signalling sleeping and waking times by using the light.

Question 38

Infradian rhythms

Answer 38

One of 3 types of biological rhythm with a frequency of one complete cycle occurring less than once every 24 hours. Eg infradian rhythms, SAD

Question 39

Outline the menstrual cycle

Answer 39

28 day cycle with 6 days of fertility, however, cycles can be shorter or longer ranging from between 24 and 35 days. Releasing the egg (ovulation) thickening of the womb lining & losing it (menstruation). These biological changes are regulated by the hormones oestrogen pre-ovulation and progesterone post-ovulation. Levels of these hormones act as endogenous pacemakers keeping the biological processes to time, an internal body clock. Pheromones of other women can act as exogenous Zeitgebers, resulting in women who live together synchronising their cycles.

Question 40

Seasonal Affective Disorder

Answer 40

Infradian disorder caused by distribution to the sleep-wake cycle and commonly occurs in the winter. Longer nights means that more melatonin is secreted from the pituitary gland via the endocrine system which the changes the production of melatonin leading to feelings of loneliness and depression

Question 41

Ultradian rhythm

Answer 41

One of 3 types of biological rhythm with a frequency of one complete cycle occurring more than once every 24 hours. A notable example are the stages of sleep, where a sleep cycle takes 90 minutes to complete.

Question 42

Briefly the sleep stages

Answer 42

Stages 1 and 2 represent the “sleep escalator” where the participant can easily be awoken, stages 3 and 4 coincide with deeper and slower delta waves whilst stage 5 represents REM sleep. REM sleep is closely associated with dreaming.

Question 43

Dement and Kleitman stages of sleep study

Answer 43

33 adults, where their caffeine and alcohol intake had been controlled, in order to remove the effect of those extraneous variables and increase the reliability of the findings. Using EEG scans, the researchers found that REM was recorded every night during each of the 126 of undisturbed sleep. Ppts were able to recall dreams when awoken during REM sleep, assumption was made between REM sleep and dreaming.

Question 44

Suprachriasmatic nucleus

Answer 44

Receives information about day light and day length from the eyes, where such information has been processed by the visual area in the occipital lobe and relayed to the SCN via the optic chiasm. The SCN then processes this information and triggers different rates of release of melatonin from the pineal gland. Increased melatonin release triggers decreased serotonin production, creating of feelings of sleepingness during the night time, where there there is little exposure to light. During the daytime when there is high exposure to light, the SCN triggers the pineal gland to release less melatonin over a longer period of time, resulting in increased serotonin production, creating feelings of wakefulness.

Question 45

Decoursey et al

Answer 45

1. Who surgically lesioned the SCNs of 30 chipmunks and compared their circadian rhythms in their natural habitat with 17 controls. The researchers found that the vast majority of the experimental group has been killed within the first 80 days after being returned to their habitat and episodes of notcturnal movement were detected within the permanent dens by radio telemetric data logging, especially in Suprachriasmatic nucleus lesioned animals.

Question 46

Evaluation Infradian Rhythm strengths

Answer 46

1. McClintock found 135 women who lived in the same dormitory at university appeared to synchronise their cycles with their friendship groups. This suggests the menstrual cycle Infradian rhythm synchronises 2. Stern & McClintock found 20 women were given pads taken from the armpits of donor women to wipe on their top lip each day. It was found that women would either shorten or extend their menstrual cycle to match the donor. Suggests infradian rhythm synchronisation Exogenous Zeitgebers

Question 47

Evaluation Infradian Rhythms: Weakness

Answer 47

1. Research found cohabiting lesbian couples did not synchronise, the optimal conditions for possible synchronisation. Countering McClintock theory